Merge tag 'block-pull-request' of https://gitlab.com/stefanha/qemu into staging

[mirror_qemu.git] / block / block-backend.c

diff --git a/block/block-backend.c b/block/block-backend.c
index 6f0a6084f1a9b9a1da41ca61fc91a4e6796ef12e..209eb075286ac6d02f239f68889f57437155178c 100644 (file)
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -390,8 +390,6 @@ BlockBackend *blk_new(AioContext *ctx, uint64_t perm, uint64_t shared_perm)
  * Both sets of permissions can be changed later using blk_set_perm().
  *
  * Return the new BlockBackend on success, null on failure.
- *
- * Callers must hold the AioContext lock of @bs.
  */
 BlockBackend *blk_new_with_bs(BlockDriverState *bs, uint64_t perm,
                               uint64_t shared_perm, Error **errp)
@@ -416,8 +414,6 @@ BlockBackend *blk_new_with_bs(BlockDriverState *bs, uint64_t perm,
  * Just as with bdrv_open(), after having called this function the reference to
  * @options belongs to the block layer (even on failure).
  *
- * Called without holding an AioContext lock.
- *
  * TODO: Remove @filename and @flags; it should be possible to specify a whole
  * BDS tree just by specifying the @options QDict (or @reference,
  * alternatively). At the time of adding this function, this is not possible,
@@ -429,7 +425,6 @@ BlockBackend *blk_new_open(const char *filename, const char *reference,
 {
     BlockBackend *blk;
     BlockDriverState *bs;
-    AioContext *ctx;
     uint64_t perm = 0;
     uint64_t shared = BLK_PERM_ALL;
 
@@ -459,23 +454,18 @@ BlockBackend *blk_new_open(const char *filename, const char *reference,
         shared = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED;
     }
 
-    aio_context_acquire(qemu_get_aio_context());
     bs = bdrv_open(filename, reference, options, flags, errp);
-    aio_context_release(qemu_get_aio_context());
     if (!bs) {
         return NULL;
     }
 
     /* bdrv_open() could have moved bs to a different AioContext */
-    ctx = bdrv_get_aio_context(bs);
     blk = blk_new(bdrv_get_aio_context(bs), perm, shared);
     blk->perm = perm;
     blk->shared_perm = shared;
 
-    aio_context_acquire(ctx);
     blk_insert_bs(blk, bs, errp);
     bdrv_unref(bs);
-    aio_context_release(ctx);
 
     if (!blk->root) {
         blk_unref(blk);
@@ -577,13 +567,9 @@ void blk_remove_all_bs(void)
     GLOBAL_STATE_CODE();
 
     while ((blk = blk_all_next(blk)) != NULL) {
-        AioContext *ctx = blk_get_aio_context(blk);
-
-        aio_context_acquire(ctx);
         if (blk->root) {
             blk_remove_bs(blk);
         }
-        aio_context_release(ctx);
     }
 }
 
@@ -780,11 +766,12 @@ BlockDriverState *blk_bs(BlockBackend *blk)
     return blk->root ? blk->root->bs : NULL;
 }
 
-static BlockBackend *bdrv_first_blk(BlockDriverState *bs)
+static BlockBackend * GRAPH_RDLOCK bdrv_first_blk(BlockDriverState *bs)
 {
     BdrvChild *child;
 
     GLOBAL_STATE_CODE();
+    assert_bdrv_graph_readable();
 
     QLIST_FOREACH(child, &bs->parents, next_parent) {
         if (child->klass == &child_root) {
@@ -812,6 +799,8 @@ bool bdrv_is_root_node(BlockDriverState *bs)
     BdrvChild *c;
 
     GLOBAL_STATE_CODE();
+    assert_bdrv_graph_readable();
+
     QLIST_FOREACH(c, &bs->parents, next_parent) {
         if (c->klass != &child_root) {
             return false;
@@ -913,25 +902,26 @@ void blk_remove_bs(BlockBackend *blk)
     root = blk->root;
     blk->root = NULL;
 
-    bdrv_graph_wrlock(NULL);
+    bdrv_graph_wrlock();
     bdrv_root_unref_child(root);
     bdrv_graph_wrunlock();
 }
 
 /*
  * Associates a new BlockDriverState with @blk.
- *
- * Callers must hold the AioContext lock of @bs.
  */
 int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp)
 {
     ThrottleGroupMember *tgm = &blk->public.throttle_group_member;
+
     GLOBAL_STATE_CODE();
     bdrv_ref(bs);
+    bdrv_graph_wrlock();
     blk->root = bdrv_root_attach_child(bs, "root", &child_root,
                                        BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
                                        blk->perm, blk->shared_perm,
                                        blk, errp);
+    bdrv_graph_wrunlock();
     if (blk->root == NULL) {
         return -EPERM;
     }
@@ -1355,7 +1345,7 @@ blk_co_do_preadv_part(BlockBackend *blk, int64_t offset, int64_t bytes,
     /* throttling disk I/O */
     if (blk->public.throttle_group_member.throttle_state) {
         throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member,
-                bytes, false);
+                bytes, THROTTLE_READ);
     }
 
     ret = bdrv_co_preadv_part(blk->root, offset, bytes, qiov, qiov_offset,
@@ -1429,7 +1419,7 @@ blk_co_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes,
     /* throttling disk I/O */
     if (blk->public.throttle_group_member.throttle_state) {
         throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member,
-                bytes, true);
+                bytes, THROTTLE_WRITE);
     }
 
     if (!blk->enable_write_cache) {
@@ -1907,11 +1897,11 @@ BlockAIOCB *blk_aio_zone_report(BlockBackend *blk, int64_t offset,
     acb->has_returned = false;
 
     co = qemu_coroutine_create(blk_aio_zone_report_entry, acb);
-    aio_co_enter(blk_get_aio_context(blk), co);
+    aio_co_enter(qemu_get_current_aio_context(), co);
 
     acb->has_returned = true;
     if (acb->rwco.ret != NOT_DONE) {
-        replay_bh_schedule_oneshot_event(blk_get_aio_context(blk),
+        replay_bh_schedule_oneshot_event(qemu_get_current_aio_context(),
                                          blk_aio_complete_bh, acb);
     }
 
@@ -1948,11 +1938,11 @@ BlockAIOCB *blk_aio_zone_mgmt(BlockBackend *blk, BlockZoneOp op,
     acb->has_returned = false;
 
     co = qemu_coroutine_create(blk_aio_zone_mgmt_entry, acb);
-    aio_co_enter(blk_get_aio_context(blk), co);
+    aio_co_enter(qemu_get_current_aio_context(), co);
 
     acb->has_returned = true;
     if (acb->rwco.ret != NOT_DONE) {
-        replay_bh_schedule_oneshot_event(blk_get_aio_context(blk),
+        replay_bh_schedule_oneshot_event(qemu_get_current_aio_context(),
                                          blk_aio_complete_bh, acb);
     }
 
@@ -1988,10 +1978,10 @@ BlockAIOCB *blk_aio_zone_append(BlockBackend *blk, int64_t *offset,
     acb->has_returned = false;
 
     co = qemu_coroutine_create(blk_aio_zone_append_entry, acb);
-    aio_co_enter(blk_get_aio_context(blk), co);
+    aio_co_enter(qemu_get_current_aio_context(), co);
     acb->has_returned = true;
     if (acb->rwco.ret != NOT_DONE) {
-        replay_bh_schedule_oneshot_event(blk_get_aio_context(blk),
+        replay_bh_schedule_oneshot_event(qemu_get_current_aio_context(),
                                          blk_aio_complete_bh, acb);
     }
 
@@ -2259,6 +2249,7 @@ void blk_activate(BlockBackend *blk, Error **errp)
     if (qemu_in_coroutine()) {
         bdrv_co_activate(bs, errp);
     } else {
+        GRAPH_RDLOCK_GUARD_MAINLOOP();
         bdrv_activate(bs, errp);
     }
 }
@@ -2384,6 +2375,7 @@ bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp)
 {
     BlockDriverState *bs = blk_bs(blk);
     GLOBAL_STATE_CODE();
+    GRAPH_RDLOCK_GUARD_MAINLOOP();
 
     if (!bs) {
         return false;
@@ -2661,6 +2653,8 @@ int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size)
 int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz)
 {
     GLOBAL_STATE_CODE();
+    GRAPH_RDLOCK_GUARD_MAINLOOP();
+
     if (!blk_is_available(blk)) {
         return -ENOMEDIUM;
     }
@@ -2721,22 +2715,19 @@ int blk_commit_all(void)
 {
     BlockBackend *blk = NULL;
     GLOBAL_STATE_CODE();
+    GRAPH_RDLOCK_GUARD_MAINLOOP();
 
     while ((blk = blk_all_next(blk)) != NULL) {
-        AioContext *aio_context = blk_get_aio_context(blk);
         BlockDriverState *unfiltered_bs = bdrv_skip_filters(blk_bs(blk));
 
-        aio_context_acquire(aio_context);
         if (blk_is_inserted(blk) && bdrv_cow_child(unfiltered_bs)) {
             int ret;
 
             ret = bdrv_commit(unfiltered_bs);
             if (ret < 0) {
-                aio_context_release(aio_context);
                 return ret;
             }
         }
-        aio_context_release(aio_context);
     }
     return 0;
 }
@@ -2901,6 +2892,8 @@ const BdrvChild *blk_root(BlockBackend *blk)
 int blk_make_empty(BlockBackend *blk, Error **errp)
 {
     GLOBAL_STATE_CODE();
+    GRAPH_RDLOCK_GUARD_MAINLOOP();
+
     if (!blk_is_available(blk)) {
         error_setg(errp, "No medium inserted");
         return -ENOMEDIUM;